The invention relates to an agricultural harvester, in particular a self-propelled forage harvester with pivotable discharge elbow for conveying the picked-up and processed crop into a loading container of a transport vehicle, wherein signals that are generated by an electro-optical device correlated with the discharge elbow are supplied to an electronic evaluation and control processing unit for automatic targeted guiding of the crop stream into the loading container.
Harvesting of agriculturally produced plants, which are used as forage or as biomass in comminuted chopped form, is performed preferably by means of a self-propelled forage harvester. By means of an appropriate harvesting attachment on the forage harvester, either the still standing plants are cut near the soil and fed to a pull-in device of the harvester or already mowed crop that has been collected in swathes is picked up from the ground of the field and also fed to the pull-in device of the harvester. Upon further passage through the forage harvester, the crop is comminuted and with the assistance of an acceleration device is further conveyed through a discharge elbow at a high speed such that it exits from the discharge elbow in a bundled crop stream and, even at greater distances, is still deposited without loss in a container.
The discharge elbow is generally mounted on the harvester so as to be rotatable about a vertical axis and pivotable about a horizontal axis. In this way, it can be swivelled between a rest position, in which it is in a lowered position and aligned approximately parallel to the longitudinal axis of the harvester, and in an operating position in which it extends, with the discharge end lifted, in particular transversely to the travel direction of the harvester. By means of a swiveling head at the discharge end of the discharge elbow, it is also possible to influence additionally the angle at which the crop is discharged.
In practice, a transport vehicle traveling next to the harvester, for example, in the form of a truck or a tractor with transport trailer, can be relatively directly loaded with the crop. In situation like turning at the headland, but also particularly at the beginning of harvesting a field with a forage harvester when next to the forage harvester there is not yet a harvested area available for parallel travel of the transport vehicle next to the forage harvester so that the transport vehicle must travel preferably behind the forage harvester, manual control of the discharge elbow for transfer of the crop as loss-free as possible into the transport container is a particular challenge for the operator of the harvester. Extremely increased throughput performances of the modern forage harvesters demand full attention of the driver due to faster harvesting travel speed and shorter fill times of the transport container.
In order to minimize the stress level on the driver and to increase the harvesting performance by avoiding downtime and loss of crop, different systems for automated filling of the transport container have been proposed. Newest systems that have already reached series production readiness are based preferably on electro-optical devices wherein optical features of the transport container are detected by means of at least one camera and the orientation of the discharge elbow is controlled such that the stream of crop is directed properly into the transport container. Such a system is disclosed already in DE 44 26 059 A1.
In practice, optical camera systems however have limits due to frequently occurring external influences such as dust, rain or lack of illumination.
In particular in special situations such as maneuvering a curve and at the beginning of harvesting a field with a forage harvester, these disadvantages are especially noticeable due to the enlarged distance between the harvesting vehicle and the transport container. In such cases, the operator must then manually intervene wherein crop losses are unavoidable at least at the time of transfer to manual control.
In further known systems, it is disadvantageous that an identification element is required on the transport containers for their recognition. In these devices, the transfer control is disadvantageously designed only for a special combination of a harvester and specifically furnished transport containers.
Accordingly, it is an object of the invention to provide a harvester with a pivotable discharge elbow that enables automatic and loss-free filling and filling as complete as possible of different unspecific transport containers in any harvesting situation.